Rivet-spinning attachment



Oct'; 30, 1928. 1,689,460

w. STUMPF RQIVET SPINNING ATTACHMENT Filed Nov. 6, 1925 2 Sheets-Sheet lOct. 30, 192s] 1,689,460 w. STUMPF RIVET SPINNING ATTACHMENT W FiledNov. 6, 1925 2 Shets-Sheet 2 Patented Oct. 30, 1928.

UNITED STATES l th-9,460 PATENT OFFICE.

WALTER STUMPF, OF BALTIMORE COUNTY, MARYLAND, ASSIGNOR TO THE BLACK ANDDECKER MANUFACTURING COMPANY, 3F TOJVSON, MARYLAND, A COBPORA- TION FMARYLAND.

RIVET-SPINNIHG' ATTACHMENT.

Application filed November 6, 1925. Serial No. 67,264.

The invention relates to an attachment in the nature of a special bitfor a portable, power-driven, rotary tool of the type most generallyused for drilling. These tools in some instances more or less modifiedas to certain details, are also used for other pur poses asscrew-driving, nut and bolt setting, bailing, grinding and valve.grinding.

The object of the present. invention is to provide means whereby apower-driven portable drill or screw-driver, etc, is immediately adaptedfor use in heading or setting rivets by spinning. The rivet spinningoporation as performed in this way, the rivets heing most generallyhandled cold, consists in applying a moderate degree of pressure to thepoints of the rivets in the direction. tending to upset and head them,at the same time rotating the pressing member at a high speed, so thatthe pressing tool, being cupshaped, the metal forming the rivet end orpoint, is caused to flow laterally and assume a convex formcorresponding to the shape of the inside of the cup.

Stationary rivet spinning machines are quite generally used. In themanufacture of automobile bodies and other comparatively bulky sheetmetal products, small rivets are driven in large numbers and headedcold. These cannot be conveniently set by means of a stationary machineon account of the diliiculty in handling the article which is beingmanufactured and have therefore been set by hand with a hammer. Thespinning operation can be performed by a workman having less skill andis much neater, quicker and more uniform, and with the presentattachment, any portable, power-driven, rotary tool of the general typereferred to can be used for this purpose.

The attachment comprises a spindle or bit adapted to be inserted in thechuck of the rotary tool, and is equipped at its lower end with aspinning tool and a work support. The spindle carries a laterallyextending guiding block or hearing member mounted thereon, the spindlebeing in effect mounted to rotate in a suitable bearing in said mem her.The work support or anvil is aligned with the rivet-spinning tool, andcarried by a sliding bar mounted in a slide bearing in said block orhearing memberparallel to the spindle hearing. The sliding bar isactuated by a hand lever by the operation of which ihe anvil is pressedupward against the work; in other words, the a. vil is caused toapproach the spinnin tool whereby the rivet head being engaged by theanvil, the,

rivet is compressed between the spinning tool and the anvil, and thetool being then rotated, the spinning operation is performed.

in the accon'ipanying drawing I have illustrated a rivet spinningattachment embody-i ing an electric drill equipped with the attachmentof the invention.

c 'c ring to the drawings by numerals, each which is used to indicatethe same or similar parts in the different figures, the illustrationincludes a portable, powerdriven, rotary tool 1, the tool illustratedbeing a small electric drill to which the rivet-spinning attachment isconnected by chuck 2. i

The rivet-spinning attachment consists of the spindle l, anvil or worksupport 5 and bearing block 6, and is provided with parallel bearingsconsisting of a rotary bearing 7 for the spindle i and slide bearing 8,in which latter is mounted the sliding bar 9 supporting the anvil 5. Therivet-spinning a. fragmentary elevation looktool 11 mounted on the lowerend of spin dle e and the anvil 5 is in alignment with the tool in thedirection of the spindle axis so that the traverse of the bar carriesthe anvil toward and from the spinning tool.

The sliding bar is actuated by a toggle 12 controlled by hand lever 13.5

Tie rotary spindle 4 is held in the bearing by a collar 1%- at the top,secured by means of a set-screw 15, and abovethe co1- lar the spindle isprovided with a reduced shank 16 adapted to enter and be secured in thechuck 2. Below the bearing block 6 the spindle 1 is provided with athrust hearing 17 which bears against the bottom face of the block, anda shoulder 18 on the shank. The tool shank below the shoulder is in theform of a fork 19 in which is mounted the spinning tool 11 on atransverse pin 20, the tool beingshown as of the regular type now inuse, consisting out a plurality of rollers forming together a concaveperipheral surface 21 with a central slot or radial opening 22.

The sliding bar 9 as shown is rectangular and the bearing 8 is likewiserectangular and ofsimilar dimensions to receive and fit the sliding bar.The latter is formed at its lower end with a transverse base bar 24 sothat the entire sliding member may be referred to as L-shaped. The anvil5 is shown as having a threaded shank 25 seated in a threaded hole 26 inthe end of the base 24 and directly in alignment with the axis of thespindle a and with the spinning tool 11. The screw-shank 26- has asuitable head 27 and is held in adjusted position by a lock nut 28.

The toggle 12 comprises a link 29 pivotally connected at 30 to thebearing block 6, and also pivotally connected at 31 at its upper end tothe hand lever 13, the pivot end of which 32" forms the second link ofthe toggle being otherwise pivoted at 33 to the sliding bar 9. The twopivot points 31 and on the handle lever link are spaced apart a distancecorresponding to the length of the other link 29. The link end 32 of thehand lever is seated in a slot 34 in the block which enters the bearingcavity 8 and exposes the sliding bar. The bearing cavity 8 is open atthe left in Figure 1, the opening being covered by a cover plate 35 heldby screws 36.

The operation of the rivet spinning tool will be fully understood fromthe description and preamble. The drill or similar tool in connectionwith which it is used and by which it is operated may be used for thevarious purposes to which it is adapted as drilling, screw-driving,grinding, boiling or the like, the attachment herein described being nomore than a special bit which can be removed and set aside with theother equipment of the tool and used when desired. With this attachmentthe portable drill or similar tool becomes adapted for use in spinningor heading rivets particularly small rivets which are set cold though itmay be adapted tor hot riveting, the work produced being neater and moreuniform and quicker, cheaper and more economical than can be produced byhand or with stationary machines, the use of stationary machines withlar e work being inconvenient, slow and comparatively expensive.

I have thus described specifically and in detail a rivet spinningattachmentembodying my invention in the preferred form in able,power-driven, rotary tool, the attach-' ment consisting of a spindlehaving one end adapted to be connected to a rotary portion 01 the toolthe other end being adapted to support a rivet spinning bit, a worksupport, a sliding bar on which said support is mounted in alignmentwith the spindle, a bearing for the sliding bar parallel to the spindle,means includin a thrust bearing mounted on the spindle supporting saidbearing for the sliding bar, and means for actuating the slidingibar tocompress the rivet between the work support and the tool.

2. A rivet spinning bit for a portable power-driven tool or other handtool comprising a spindle having at one end a shank adapted to beengaged by a bit chuck and at the other end a rivet spinning tool, ananvil supported by the spindle in alignment with the rivet spinningtool, and means for moving the anvil toward the tool to compress a rivetbe tween the tool and the anvil.

3. A rivet spinning bit comprising a shank adapted to be engaged by abit chuck, a rivet spinning tool carried by and connected to said shankto be rotated thereby, a work support also carried by the shank andmeans for controlling the relative position of he work support and l itwhereby a rivet may be compressed between the rivet spinning tool whichis applied to the point of the rivet and the work support which isapplied to the head of the rivet.

4. A rivet spinning bit for a portable rotary tool, the bit having ashank adapted for connection with a rotary portion of the tool, a rivetspinning tool connected to said shank to be rotated thereby, a guide,means supporting the same on the shank, a sliding bar mounted therein tomove parallel to the axis of said rotation of the rivet spinning tool,an anvil carried by the sliding bar in alignment with the spinning toolin the direction of the said axis. thereof, and means carried by the bitfor actuating the sliding bar to cause the 1 v. a no: c1 21o t V vnerere no an il to 13 ii ll 0ol v by th 1 1 being applied to the point oi.the rivet and the anvil to the head, the rivet may be compressed betweenthe tool and the anvil.

Signed by me at Baltimore, lviaryland, this 3 day of November, 1925.

WVALTER STUMPF.

